Very sad. (Is any supplemental Medical required in Canada for aerobatic displays at public airshows?)
The Report on this one will be interesting. I do wonder how many pretty elderly and relatively low-hour pilots in vintage aircraft get a little carried away at such events and just 'push the envelope' too far. The pilot of the Shoreham crash in the UK was licenced to perform aerobatic manoeuvres above 500' or fly-pasts at 100'. The loop he performed that day was commenced at 200' AGL... with very similar results.
We'll see.